Measured-service telephone system.



F. NEWFOR TH, In. MEASURED SERVICE TELEPHONE SYSTEM.

I APPLICATION FILED-AUG.25, I913- Patented June 13, 1916.

2 SHEETS-SIIEET I.

A/J/E/VTOR:

I/V/T'NESSES w mm F. NEWFORTH, In.

MEASURED SERVICE TELEPHONE SYSTEM.

HUT/M55355 saeaa.

FRANK NEWFORTH, an.) or LJLVERPOOL, ENGLAND, ASSIGNOR TO anrom'rro annorraio COMPANY, or CHICAGO, ILLINOIS, a ooaromrron or ILLINOIS.

MEASURED- SERVICE TELEPHONE SYSTEM.

To all whom it may concern:

Be it known that I, FRANK-NEWFORTH, Jr, a citizen of the United States of America, and resident of Liverpool, England, have invented certain new and useful Improvements in Measured-Service Telephone Systems, of which the following is a specification.

My invention relates to measured service telephone systems, and more particularly to systems in which each subscribers line is provided with a service meter 'located at the central office. g I

The object of my invention is to provide such a meter which is operated over the release trunk, and to provide means for preventing the meter from'being operated more than once for each call, and to also provide means whereby the meter will not register when connection is made with an operators set. I

These and-other objects of my invention will be more readily understood by reference to the. accompanying drawings, in which I have illustrated my invention in connection with anautomatic telephone system of a particular type, although it will, of course, be understood that my invention is not limited to such a system. I

In the drawings Figures 1 and 2 represent a complete connection between a calling telephone at the substation A. and a called telephone at the substation A in a system embodying the principles of my invention.

Fig. 3 shows a traffic trunk leading to an operators talking set comprising the necessary relays and signal. p

I In Figs. '1 and 2 I have shown the line switch extending oonn'ectiondirectly to the connector switch. These connector switches ordinarily have access to but OHQ'llllIldI'Gd. lines, but if the exchange is of larger size it is merely necessary to insert first, second or third selectors between the subscribers individual switches and the connectors, in a manner well-known and understood in the art. My improvements are contained solely in the subscribers individual switch and the connector switch, and accordingly to simplify the disclosure I have merely illustrated these two switches. The automatic substation A (Fig. 1) comprises the usual receiver 2, transmitter 3, ringer 4: and condenser 5.

Being an automatic substation, it is also provided with a suitable call-sending mechanism for controlling the automatic switches,

which mechanism is represented diagrammatically by a pair of impulse springs 6 and 7 and an impulse wheel 8, which latter may be controlled in a well-known manner by a" dial provided with finger holes in such a way that the impulse springs may be momentarily separated anumber of times corresponding to the respective digits of the number ofthe called subscriber.

The subscribers individual switch C is of the general type of subscribers switch shown in British patent to R. W. James No. 26,301

of 1906, more closely resembling, however,

the particular type shown in British patent to T. G. Ma1'tin No. 1419 0131910.. This line switch comprises among other details a plunger (not shown) attached to the endof a so-called plunger arm9 which is controlled by a magnet 10, which magnet comprises an operating winding 11 and a holding winding 12. This magnetalso controls the cutoff armature 13. The winding 11 operates both the plunger arm 9 and the armature 13, while the winding 12 is strong enough to operate only the armature 13 and to hold the plunger arm 9 in its operated position. When the plunger arm 9 is operated, its plunger is forced intoa bank of contact springs, forcing the springs 14, 15,16 and 1 into contact with the springs 18, 19, 20 and 21. respectively. Although only one set of springs (14 to 21) is shown, each line switch is provided with a plurality of such sets, each set forming the terminal of a trunk line leading to a connector switch I. Each trunk line is connected in -multiple with. the corresponding springs of all the.

line switches of thegroupwhich' is controlled by the master switch D. The switch C is controlled by the subscriber through the medium of the line relay 22, which relay is preferably slow acting-that is, slow to release its armature upon deenergizing. A metering device is shown at M for the pur pose of registering the calls that are completed and answered by the called party.

The master switch D comprises a starting relay 23, a locking magnet 24 and a restoring relay 26. The usual plunger guide shaft 27, through the medium of which the master switch controls the plungers, is connected with a rotary shaft 27 in such a manner that, as said shaft is rotated back and forth, the plunger guide shaft 27 is oscillated about said shaft 27 a as an axis. The

shaft 27 is adapted. to be rotated in one direction by a spring 28 and in the other direction against the tension of said spring by a solenoid 29. Secured to the shaft 27" is a cam member 30 provided along its outer edge with notches 31, one for each trunk line to which the line switches have access. The

shaft 27 is normally locked against rotation in either direction by the engagement of the lever 32 with one of the notches 31.

The lever 32 is controlled by the armature of the relay 24 in such a manner that when said relay is energized the lever is withdrawn from the, cam 30 so as to unlock the The speed of rotation of the shaft 27. shaft 27 and the plunger guide shaft 27 is regulated by means of ,a suitable governor 33." The spring 34 of the relay 26 is locked in its operated position by the engagement of the spring 34 with the detent on the under side of the spring 35. The springs are unlocked by the arm 36 when the shaft 27 has reachedvthe limit of its travel in one direction. When the shaft 27 reaches the limit of its travel in the other direction, the arm 37 forces the spring 38 into engagement with the spring 39. The master switch D is also provided with a bank of contacts a, one for each trunk line. A wiper 40 keeps the common segment 41 in electrical connection with 'the individual contact a corresponding to the trunk line before which the idle plungers are resting. In general, the operation of the master switch is as follows: VVhenever a trunk line is seized by a line switch, the relay 24 is energized to unlock 'the shaft 27, the spring 28 thereupon rotating the shaft 27* to cause the plunger guide shaft 27 to move the idle plungers away from the trunk just seized and to an idle trunk line. When an idle trunk is reached, the relay 24 denergizes and again locks the shaft. When the plungers reach the last trunk, the arm 37 forces the springs 38and 39 together, so that when this trunk is seized, the circuit of the relay 26 may be closed. The relay 26 energizes and its springs become locked in their operated positions, thereby closing the circuit of the solenoid 29, which rotates the shaft 27 backin the opposite direction to bringall the plungers which are in engagement with the plunger guide shaft back to a position opposite the first trunk line andv to restore tension to the spring 28. When the plungers reach their starting positions,

the arm 36 unlocks the spring of the relay 26, which permits the solenoidto deenergize provided With a switch sha'ft'carrying the wipers'57, 58 and 59 controlled by the vertical and rotary magnets 60 and 61. The

usual side switch comprising the wipers 62, 63, '64 and is controlled by the private magnet 66 in a well-known manner. The magnet 67 is the usual release magnet and the line relay 68 is connected to the line through 'the reversing springs of the batteary-reversing relay 68*, through the winding of which, togetherwith the winding of the relay69, the called line is supplied with talking current. The ringer relay 70 is the means by which the application of ringing du'rrent to the called line is controlled.

At Q, there is shown a 'busy signaling machine which is connected through the contact of springs of the relay 73-with the second-position contact of the side switch wiper 63, the function of whichmachine is to send back a busy tone to the calling subscriber should the line he is calling prove to be busy. For the purpose of supplying battery current for operating the central ofiice apparatus, there is provided a battery B having one pole grounded at G. A second battery B is also provlded and it will be seen that it has the opposite pole grounded to that of the battery B. The function of this battery B is to be instrumental in operating the meter M (Fig. 1) upon the operation of the springs 74 and 75 of the relay 76, whereby said battery B is placed in series with the battery B. The meter magnet 77, unlike the usual meter magnet, has but one winding and is operated by an impulse transmitted over the release trunk.

In the event of a subscriber having his telephone removed or taken out of service for nonpayment, or for numerous other reasons, hisline, or rather the linethat was formerly his, is disconnected from the central office apparatus and the contacts of the connector banlr constituting the terminals of said subscribers line are temporarily wired to what is known as a traffic trunk, said trunkand contact being shown in Fig. 3. Therefore, upon a subscriber attempting to call a subscriber whose telephone instrument has been taken out of'ser'vice, he will signal the operator at the exchange, who

will give him the necessary information. It is not desirable that such 'a call as this be charged to thecalling subscriber. In a sysreceiver off the switch-hook by the so-called back-bridge relay energizing. Arrangements are therefore made necessary whereby the operator, upon operating her key K ,to respond to the signal given by a subscriber calling the subscriber whose line has been disconnected, will not operate the meter magnet 77 (Fig. 1).

A'general description of the central ofiice" apparatus having been given, it will now be explained how connection can be made between a calling substation A and a called substation A. We will assume the number of the called subscriber to be 20. Since the automatic switching apparatus disclosed herein is in general well known in the art, and is described in the publications herein referred to, its operations will be explained in a more or less general manner. ,Upon the removal of the receiver from the switchhook at the substation A, the talking circuit of the substation is bridged across'the line conductors 80 and 81 by the hook-switch springs 82 and 83, whereby the circuit of the line relay 22 of the switch C is closed. This circuit extends from ground G through the springs 84 and 85, substation A, springs 86 and 87, relay 22 and through battery B to ground G. The relay 22, upon energizing, closes the circuit of the operating winding 11, which energizes and disconnects the relay 22 from the line and thrusts the plunger into the bank terminals of the trunk before which it is being held by the master switch. Upon the springs 14 and 18, and 17 and 21 being pressed together, the line connection is extended to the connector switch 1, thereby energizing the line relay 68, the circuit being tracedfrom ground Gr through the lower winding of the relay 68, springs 191 and 189, conductor 110, bank springs 21 and 17, through. the telephone at substation A, back over the conductor 81, springs 14 and 18, conductor 109, springs 190 and 192 and through the upper winding of the relay 68 to battery B. After the relay 22 deene'rgizes, the switch C is maintained in its operated position over a hold- .in'g circuit closed to ground at the relay 76 of the connector I. This ground is connected to the release trunk v129 through the springs 161 and 1.62 of the slow-acting relay 160,

which is energized as a result of the energization of the line relay 68. The circuit is as follows: from ,ground G through the contact of springs 209 and 74, springs 162 and 161, conductor 129 bank springs 19 and 15 of the line switch C, thence through the coil 12 in multiple with the meter magnet 7 7 and the contact 77 to the battery lead 100, thence through battery B to ground (i (Fig. 2). This circuit through the coil 12 serves to maintain the switch C in its operated posideenergized.

tion after the relay 22 attheswitch C has I Although the meter magnet 77 receives current from battery B over the circuit above traced, it is not operatively energized, because it is so wound andadjusted as not to be operated by the battery B alone. \Vhen the springs 16 and 20 (are pressed together by the operation of the switch C, a circuit is closed from ground G through said springs: contact point 101,

wiper 40, common segment 41 and the relay 23 to the battery lead 100. The relay 23, upon energizing, completes an energizing circuit for the relay 24, which operates to open the springs 102 and 103 and to close thesprings 103 and 104. The opening of the springs 102 and 103 disconnects the op erating windings of all the switches'of the. group to which the switch C belongs from the battery lead 100. The closure of the springs 103 and 104 is without any particular function at this time. The relay 24,

upon energizing, also operates to withdraw the locking arm 32 from the cam 30, thereby releasing the shaft 27 and permitting it to be rotated by the spring 28 to cause the plungers of the idle line switches to be moved away from the trunk line seized by the switch C. lVhen the plungers have been moved away from this trunk line, the wiper 41 passes olf the contact, and should the next trunk line be idle, the relay 24 de energizes and permits the arm 32 to drop into the next notch in the cam 30, thereby bringing the shaft to rest with the plungers standing opposite the. next trunk line. However, should the next trunk be busy, the relay 23 remains energized until the next notch in the cam 30 is passed. When the plungers of a line switch are carriedto the last trunkfline terminal, the arm 37 presses .the springs 38 and 39 into contact, thereby extends from ground G through the contact of the springs of the relay 23, springs 38 and 39, relay 26 and springs 104 and 103 to battery B. The relay 26, upon energizing, closes the circuit of the solenoid 29, which, upon energizing, operates to restore the plunger shaft and plungers back to their starting positions. When the relay 26 is energized, its springs become locked in their operated positions .by the spring 35. -lVhen the plunger shaft reaches its starting position, the arm 36 unlocks the springs of the relay 26, thereby permitting the sole noid to denergize. It will thus be seen that the plunger shaft is caused to complete its entire movement once, thereby causing all the idle plungers which it controls to become locked in engagement therewith.

It will be remembered that by the operation of the switch C the line connection has been extended A through tothe connector I and the line relay 68 is energized, together with the slow-acting relay 160, which latter prepare a circuit for the vertical magnet 60. The subscriber now operates his dial. for the first digit 2, whereby the springs 6 and 7 at the calling, device aremomentarily separatedtwice, breaking the circuit of the line relay 68 a corresponding number of times. Upon thelarmature, falling back twice, two impulses are sent through the vertical magnet to raise the switch shafttwo steps opposite the row or level of contacts in which the line terminals leading to the subscribers telephone are situated. This circuit is traced as follows: from ground G contact of the springs 163 and 164, and 165 and 166, through the private control relay 167, vertical magnet 60 and the side switch wiper 65 to battery, thence to ground G. Upon the vertical magnet being twice momentarily energized, the

. switch shaft is raised two steps in the usual terruptions of its circuit.

manner. Upon I the relay 167 becoming energized, a circuit is closed through the relay 168 and the private magnet 66 in series. The relay 167 being slow acting does not deenergize during the momentary in- The private magnet 66,"as is well known, is energized to prepare the side switch for escapement to second position, while the relay 168' opens the line while impulsesare being delivered. After the last impulse of this series has been transmitted, the private control relay 167 denergizes and breaks the circuit of therelay 168 and the magnet66, thereby allowing the side switch to ,pass to second position. Upon the side switch wiper 65 passing to second position, battery current-is disconnected from the vertical magnet-60 and connected with the rotary magnet 61. When the calling device is o erated for the next digit 0, the relay 68 eenergizes ten times, each time closing the circuit, of the rotary magnet 61. This circuit is traced from groundGr through the springs 163 and 164, 165 and 166, relay 167, springs 171 and 170, rotary magnet-61 and the side switch wiper-65 to battery B. The rotary magnet, receives ten impulses to ro-- tate the shaft wipers around 'ten stepsonto' the contact of the desired line. The private magnet 66 and the slow actin relay 168 are energized at the first impu se and remain so until the last impulse has been transmitted, due to the energization of the private control relay 167.

a When the private magnet 66 finally deenergizes, the side switch passes to third position. Therelay 168 being slow acting does not deenergizeimmediately when its be'ing pressed together by th circuit is broken. Therefore the lines are kept open at the springs 173 and 174 ashort time after the side switch passes to third position." The object of this is to eliminate the possibility of the ringing current opthe side switch wiper 64 passes tothird position, a guarding potential is placed'on the private contacts of the called line and a circuit is closed through the cut-off winding 175 at the line switch C. This circuit ex tends from ground G through the side switchwiper 64, private wiper 58 and the winding 175 to battery B. The winding 175,-upon energizing, I attracts the armature '17 6, which operates -to' disconnect the switch C. from the line. Upon the .side switch wiper- 65 passing to third position, battery current is supplied to the ringing relay 70. This circuit istraced from ground G through the interrupter 177, ringing relay 70, springs 178 and 179 and" the side switch wiper 65 to battery B. The relay 7 O has its circuit intermittently opened and closed by the interrupter 177 to alternately disconnect the called line fromthe calling line and to throw out over the called line alternating current from the ringing generator R to ring the called subscribers bell.

When the calledsubscriber removes his receiver from the switch-hook, or as soon thereafter as the ringing relay 7O denergizes if it is energized at the time, a circuit is closed from ground G through the backbridge 68, springs 182 and 183 and 174, line wiper 59, springs 187 and'l88 at the substation A, line wiper-57, springs 173,

184' and 185 and the relay 69 to battery be seen, transposes the negative side of the 9 line to the positive'pole of battery and the positive sideof the line to the negative pole of the battery through the respective windings of the line relay 68.- This operation can be utilized in a semi-automatic system to operate the supervisory signals, or for any other purpose. Upon th springs 204 g relay 69, a circuit is closed through the ring cut-ofl relay 202 and the relay '76 in circuit extends from, ground the shaft-controlled contact 203, relay contact 204,. relays 76 and 202 and the side series, which G through I switch wiper 65 to the battery lead 1 00.

The relay 76, upon energizing, disconnects ground G from the hol' ing circuit extending back through the preceding switches and at the same time connects said circuit polarity to that of the battery B, the two 1 batteries are connected in series over the circuit traced. This increases the current. 1n the meter magnet, 77 of the calling line sufliciently to cause it to attract its arma- Y ture to advance the meter one step to regis ter the call.

The relay 202 at the connector switch, upon energizing in series with the relay 76, operates to, open the circuit of the ringing relay 70 at the springs 178 and 179 and closes a locking circuit for itself from round G through the shaft-controlled contact 203, springs 205 and the Winding of the relay 202 vto the battery lead 100. The closing of the spring contact 205 of the relay 202 also short-circuits the relay 76, which deenergizes to disconnect battery B from the holding circuit and the meter magnet 77 and restore the connection to ground G It is thus seen that the relay 76 operates to transmit only a momentary impulse from battery B through the meter magnet of the calling subscriber, said magnet, however, being so adjusted that after it has once been energized it may be held up by the battery B al0ne,-so that it does not fall back after battery B is disconnected, but remains in an energized position until the connection is released, thereby eliminating any possibility of the meter being operated morethan once for each call. The a magnet 76 of the connector is preferably rendered slow to deenergize by a ring of copper around one end of its core, or by any other desired means, so as to transmit a sufliciently long impulse rom battery B to insure thatthe meter shall be fully operated. Since the relay 202 remains locked up and the contact 205 closed until the connection' is released, itv is now impossible for. the called subscriber tb operate the relay 7 6 more than once by moving his. receiverup and down, and consequently no .more than a single impulse can be transmitted from battery B for eachcall. I The resistance 215 is included in the lead of the battery B simply as a protective means to prevent short-circuiting the battery when all three springs of the relay 76 are in contact while it is energizing and denergizing.

In order to release the connection the calling subscriber hangs up his receiver, thereby breaking the circuit of the line relay 68 magnet 67.

of the lamp 209 is closed from ground (Fig. 2) at the springs 82 and 83. The line relay 68 deenergizes and breaks the circuit of the slow acting relay '160 at the spring 163. Upon the relay 160 deenergizmg, a circuit is closed through the release This circuit is traced from ground G through spring 163 and 164:, back contact of the spring 165, normal spring 260 and through the release magnet 67 to battery B. The release magnet, upon energizing, withdraws the holding pawl from the switch shaft, allowing same to rcturn by'means of a spring and gravitation to its normal position. The deenergization of the relay 160 also takes ground oii the release trunks by the opening of the springs 161 and 162, thereby breaking the circuit of v the holding winding 12 of the line switch C.

When the winding 12 deenergizes, the

' plunger is retracted from the bank terminals, restoring the switch 0 to normal position.

As has been heretoforestated, should a subscribers telephone be put out of service, his line switch is disconnected from the line and the contacts of the connector bank representing his number are wired to what is known as a trafiic trunk (shown in Fig. 3) terminating at the information I desk.

Assuming now that a subscriber at the sub-- 1 station A is calling a subscriber whose telephone has been disconnected, the Wipers 57, 58 and 59 coming to rest on the desired con tacts and the side switch wipers passing to third position, the line connection, instead of being cut through to the telephone, would light the lamp 209 at the operators desk (Fig. 3) in the following manner: When the wipers 57 and 59 stop on the contacts 78 and 79, a circuit is closed through'the relay 210, part of which has already been traced through the back-bridge relays 6 8 and 69. The resistance of the relay 210 is high, enough to prevent sufiicient current flowing through these relays to operatively energize them, Therefore, the direction of the flow of current over the calling line is not reversed, neither is the relay 76 energized to register the call. One side'of the relay 210 is wired to a normally closed contact. Upon this relay energizinggthe circit 21 through contact of the springs 212 and springs 213 and 214, through said lamp 209 to battery B When the operator sees the signal she operates her key K during one of the pauses between application of ringing currentto the line to bridge her telephone set across the line at the springs 216 and 217 and asks what number the subscriber is calling and thus closes the circuit of the relay 218. This circuit is traced from ground Gr through the springs 219 and through said relay to battery B Upon the relay 218 energizing, the circuit of the lamp springs 213 and 214, 'When once the relay 218 is energized, it remains so all the time the relay 210 is energized, for a circuit is formed from gIOllIldG through the contacts 212, springs 213 and-220 and through said relay to battery B Upon the springs 211 breaking contact the resistance coil 221 is included in the bridge across the line, to p I contact of 'theb'usy line provides a holding increase its impedance "while conversation is belngcarrled on. Also, upon the key K being operated, an impulse is sent through the relay 225 by means of the springs 226,

227 and 228, which momentarilyenergizes said relay to place a direct ground connection on the contact 78, thereby closing an energizing circuit for the connector backbridge relay 69 without energizing the .re-

lay v68. 'The relay .225 being slow acting' maintains its magnetism for an' appreciable length of time to give the back-bridge re.- lay 69a chance to operatively energize. The circuit of the back-bridge relay is traced from ground G 5 through contact of'the V s rings229, contact 78, springs 173'and185] I when the ringing relay is .deenergized) and through the relay 69 to battery .13.

Upon the relay 69 momentarily energizing, a circuit is closed from ground G through the normal springs 203 contact of springs 204, s rings 201 and 200, throughthe ring. cut-o relay 202 and the side switch wiper to battery B. It will 'be seen that this circuitldoes not pass throughthe relay 76 a as it doeswhen a called subscriber answers, owing to the fact that the relay 68 is-not energizedand the relay 76 is therefore shortcircuited at the springs 200 and 201. There-v ;fore, no impulse is transmitted over the holding trunk from battery B to operate the calling subscribers meter when the operator answers the bell, but the relay 202 is energized in the usual manner to open the circuit of the ringing relay 70. It is thus seen that upon aparty calling a subscriber whose line leads to the information v desk, he signals the information operator,

and when the operator answers, the ringing current is cut off without operating the calling. subscribers meter, whereas, when the connection is obtained with a ,subscr'ibers line as has been already explaifned, the act of the called, subscriber removing his, re 'ceiver' from the switch-hook to answer-a call a both operatesv the meter and cuts off the ringing current.

Whenever a line i'sbusy, eitherby reason of having made a call or by reason of having been, called, there is a guarding ground potential upon its connector private bank 7 contacts. When the wipers'of a connector .are rotated onto the contacts of a busy line, 'a ground :potential is extended from the grounded private bank contact of said line through the private wiperr58, side switch wiper 64 (which is then in second position),

circuit for the private magnet 66and does not'perm'it it to'deenergize, while at the same time the relay 73 becomes energized in series with the private magnet 66 and the relay 168, Since the private magnet 66 doesnot denergize' after the last digit is called, the side switch remains locked in second position and noconnection is completed between the calling line and the busy called line.-.' Therelay 73, upon energizing, transfers the locking ground for itself and the private magnet from the guarded private bank contact of the busy line to the ground G by way of the springs 203, 146 and 155. The relay 73, upon energizing, also completes} a connection from the busy signaling machine Q through the springs 71 and 72 andthe side switch wiper 63 to the "calling called, the ringing current is cut off without operating the subscribers meter, Furthermore, it will be seen that this cutting off of the ringing current is not dependent in any way upon'the differences in time required to operate various relays, as has heretofore been the case, but is provided by the provision of two back-bridge relays, both of which are required to be energized to operate the meter, while only one need be energized to cut ofi theringing current. vWhen a subscriber answers, he operates both relays, and when the operator answers, she operates but one. p p

While I have illustrated one specific, embodiment of my invention, it is, of course, to be understood that I do not'wish to be limitedto the exact construction shown and described, but my invention is capable of use in connection vwith other automatic or semiautomatic systems, I

What I claim as my invention-is:

1. In a telephone system. a plurality of subscribers lines, automatic switches for establishing connection between two of said lines, a release circuit in said switches, a

, line to notify the calling subscriber that the meter for registering the calls controlled over said circuit, an operating magnet therefor, means for transmitting current from abattery through said magnet during the establishment of said connection, and means for inserting another battery in said release circuit for transmitting a strengthened impulse through said magnet to operate the same upon the response of the called subscribe'r.

3. In a telephone'system, a plurality of 5 subscribers lines, a trunk-selecting switch individual to each of said lines, automatic means for extending a connection from the trunk-selecting switch of any line to a desired called line, a release circuit for said uneans, a meter for registering the calls associated with each line controlled over said re lease circuit, an operating magnet therefor, means for transmitting current from a battery through said magnet during the establishment of said connection, and means for inserting another battery in said release circuit for transmitting a strengthened impulse througlnsaid magnet to operate the same.

4. In a telephone system, a plurality of subscribers lines, a trunk-se ecting switch individual to each of said lines, automatic means for extending a connection from the trunk-selecting switch of any line to a desired called line, a release circuit for said means, a-meter for registering the calls associated with each line controlled over said release circuit, an operating magnet therefor, means for transmitting current from'a battery through said magnet during the establishment of said connection, and means for inserting another battery in said release circuit for transmitting a strengthened impulse through said magnet to operate the same upon the response'of the called subscriber.

5. In a telephone system, a plurality of 7 subscribers lines, automatic switches for establishing connection between twoof said lines, a meter for registering the calls, an operating magnet therefor, means for transmitting current of one strength through said magnet during the establishment of said connection, and means for opening the first circuit of said magnet and for closing a second circuit throughsaid magnet to transmit relay to prevent a -second operation of said a strengthened impulse through the same to cause its operation.

6. In a telephone system, a plurality of subscribers lines, automatic switches for establishing connection between two of said lines, a meter for registering the calls, an operating magnet therefor, means for transmitting current ofone strength through said magnet during the establishment of said conmotion, and means for opening the first circuit of said magnet and for transmitting a strengthened impulse through the same to operate said magnet upon the response of the called subscriber. p

7. In a telephone system,'a plurality of subscribers lines, means including an automatic connector switch for establishing a connection between two of said lines, a meter for-registering the calls, an operating magnet therefor, means for transmitting current of one strength through said magnet in the establishment. of said connection, a relay associated with said connector, means for momentarily energizing said relay upon the response of the called subscriber, means controlled by the energization of said relay for transmitting a strengthened impulse through said magnet to operate the same, and means for then short-circuiting said magnet.

8. In a telephone system, a plurality of subscribers lines, means including an automatic connector switch for establishing a connection between twoof said lines, a meter for registering the calls, an operating magnet therefor, a relay associated with said connector, ineans for momentarily energizing said relay upon the response of'the called subscriber, means controlled by the energization of said relayfor operating said magnet, and means for then short-circuiting said relay to prevent a second operation of said magnet.

9. In a telephone system, a plurality of subscribers lines, means including an automatic connector switch for establishing a connection between two of said lines, two back-bridge relays for said connector, a service'meter, a source of ringing current, means for connecting said ringing current with the called line, means controlled by the energization of both of said relays for operating said meter, and means controlled by the energization of but one of said relays for cutting oft" said ringing current.

10. In a telephone system, a plurality of subscriberslines, means including an automatic connector switch for establishing a energization of bothof said relays for oper- 139 ating said meter, means controlled by the" energization of but one of said relays for cutting off said ringing current, an operators set to which said connector switch is adapted toextend connection, means controlled upon the response of the. called subscriber foroperating both of said relays, and

means controlled upon the response'of the.

operator for operating but one of said relays,

, whereby the response of the operator does not operate said meter.

11. In a telephone system, a calling and a called subscribers line, a connector switch for establishing connection with the called line, automatic switches for extending con-' nection fro'nr a calling line to said connector switch, a release trunk extending to said connector over which said automatic switches are released, a meter for registering calls, an operating'magnet therefor, means for transmitting current of one strength through said magnet during the establishment of a connection, and means fortransmitting a strengthened impulse over said release trunk through said magnet to operate the same.

12. In a telephone system, a calling and a called subscriberls line,-a connector switch for establishing connection with the called line, automatic switches for extending con- @IIBCtiOIl from acalling line to said connector switch, a release trunk extending to said connector over whlch said automatlc switches are released, a meter for registering calls, an operating magnet therefor, and means for opening the first circuit of-said magnet and closing a second circuit through said magnet over said release trunk to transmit a strengthened impulse through the magnet over said release trunk to transmit a strengthened impulse through the magnet to cause its operation. V

13. In a telephone system, a calling and a called "subscribers line, a connector switch forestablishing connection with the called line, automatic switches for extending connection from a calling line to saidconnector switch, a release trunk extending to said connector over whlch said automatic switches are released, a meter for reg stering calls, an

operating magnet therefor, means for'trans 'mitting current of one strength through said magnet during the establishment of=a connection, a relay associated with said connector, means for momentarily energizmg said relayupon the response of 21 called sub-,

scriber, and means controlled by the energization of said relay for transmitting a strengthened impulse over the release trunk through said magnet to operate the same.

14.. In a telephone system, a'calling and a called subscribers line, a connector switch for establishing connection withthe called line, automatic switches for extending con' nection from a calling line to said connector switch, a release trunk extending tosaid connector overwhich said-automatic switches are released, a meter for registering calls, an

operating magnet therefor, means for transmitting current of one strength through said magnet during the establishment of a connection, a relay associated with said connector, means for momentarily energizing sald relay upon the response of a called subscriber, means controlled by the energization of said relay for transmitting a strengthened impulse over the'release trunkthrough said magnet to operate the same, and mearls forthen short-circuiting'said relayto prevent a second operation of said magnet. o

15. In a telephone system,a calling and a calledysubscribers line,-- a connector switch for establishing connection with the called line, automatic switches for extending connection from a calling line to said connector switch, a release trunk extending to said connector over which said switches are released, a meter for registering calls, an operating magnet therefor, a relay associated with said connector, nfeans for automatic :mom ntarily energizing said relay upon the response of the called subscriber, means controlled'by the energization of said relay for transmitting an impulse over said release trunk to operate said magnet, and means for then short-circuiting said relay to prevent a second operation of said magnet.

16. In a telephone system, a plurality of subscribers lines, means including an automatic connector switch for establishing connection between two of said lines, two backbridge relays for said connector, a service meter, an operating magnet therefor, a source of ringing current, means for connecting said ringing current with the called line, means controlled by the energization of but one of said relays for cutting oil said ringing current, and means controlled by the energizationof both of said relays for transmitting a momentary impulse through said operating magnet to thereby operate said service meter. 7

17. In a telephone system, a plurality of subscribers lines, means including an automatic connector switch for establishing connectionbetween two of said lines, two backbrldge relays for saldconnector, a service meter, an operating magnet therefor, a

source of ringing current, means for connecting said ringing current with the called line, means controlled by the energization of but one of said relays for cutting off said ringing current, means controlled by the energization of both of said relays for transemitting a momentary impulse'through said operating magnet to thereby operate said servlce meter, an operators set to whichsald connector switch is adapted to extend. connection, means controlled by the response of a subscriber for operating both of said relays, and means controlled by the-response of the operator for operating but one of said relays, whereby the'response of the operator does not operate said meter.

18. In a telephone system, a pluralityof subscribers lines, automatic switches for establishing connection between two of said lines, a meter for-registering the calls, an

operating magnet therefor, means for transmitting current of one strength through said magnet during the establishment of said connection, and means for opening the circuit of said magnet and for transmitting current of different strength through the same to operate said magnet upon the response of the called subscriber.

19. In a telephone system, a plurality of subscribers" lines, automatic switches for establishing connection between two of said lines a meter for registering the calls, an operating magnet therefor, means for-transmitting current of one strength through said magnet during the establishment of said connection, and means for momentarily opening the first circuit of said magnet and for closing a-second circuit through said magnet to transmit a current of different strength through the same to cause its opera til tion.

20. In a telephone system, a plurality of subscriberslines, means including an automatic connector switch for establishing a connection between two of said lines, a meter for registering the calls, an operating magnet therefor, means for transmitting current of one strength through said magnet in the establishment of said connection, a relay associated with'said connector,means for momentarily energizing said relay upon the response of the called subscriber, means con-' trolled by the energization of said relay for transmitting current of difierent strength through, said-,magnet to operate the same,-

and means for short circuiting said relay to prevent a second operation of said magnet. 4 21. In a telephone system, a calling and a called subscribers line, a connector switch for establishing connection with the called line, automatic switches for extending connection from a calling line to said connector switch, a release trunk extending to said connector over which said automatic switches are released, a meter for registering calls, an operating magnet therefor, means for transmitting current from a battery through said magnet during the establishment of a connection, and means for inserting another battery in said release trunk for transmitting current of diiferent strength over said release trunk through said magnet to operate the same.

22. In a telephone system, a calling and a called subscribers line, a-connector switch for establishing connection with the called line, automatic switches for extending connectionfrom a calling line, to said connector switch, a release trunk extending to said connector" over whichv said switches are released, a meter-for registering calls, an operating magnet'therefor, a circult for said magnet and means for mo mentariiy opening said circuit and closing a second circuit through saidmagnet over 1 said release trunk llOlZI'ELIlSHlli} a current of ing calls, an operating magnet thererfor,

mcans for transmitting current from a battery through said magnet during the establishment of aconnection, a relay associated with said connector, means for momentarily energizing said relay upon the response of a called subscriber, and means controlled by the 'energization of said relay for inserting another battery in said release trunk for transmitting current of a difi'erent strength over said release trunk through said magnet to operate the same.

2st. In a telephone system, a plurality of subscribers lines, means including an automatic connector switch for establishing connection between two of said lines, two backbridge relays for said connector, a service meter, an operating magnet therefor, a source of ringing current, means for connecting said ringing current withthe called line, means controlled by the energization of but one of said relays for cutting ofi said ringing current, and means controlled by the energization of both of said relays for transmitting current of a 'difierent strength to said operating magnet to thereby operate the said service meter.

25 In a telephone system, a calling and a called subscribers line, a connector switch for establishingconnection with the called line, automatic switches for extending connection from the calling line to-v said connector switch, a release trunk extending to said connector over which said automatic vswitches are released, a meter for registerautomatic the called switch, a release trunk extending to said connector over which said automatic switches are released, a meter for registering calls, an operating magnet therefor, a first circuit for said magnet, means for closing a second circuit through said magnet over said release trunk and for opening said first circuit to transmit a current of differvent strength through said magnet to cause its operation.

Signed by me at Liverpool, England, this 31st day of July, 1913.

FRANK NEWFORTH, JR. Witnesses:

ALEX. E. WALKER, H. WATSON. 

